I'm running both soft pack and hard packs.

Soft packs are more prone to cell puncture than hard packs.

You often can only race with hard packs.

At my club soft packs are not even allowed. I bought a 1 mm pvc plate and cut out sides and ends for my soft packs and wrapped it with duct tape. They are now a lot thougher than normal hardpacks and adds some 75g to the weight.

Probably not all tracks will allow to run "modified" soft packs, and many tracks only allows ROAR approved packs.

I know many other that are using soft packs in their 1/10 and 1/8 buggies and never had an issue.

Just be aware of tear and wear, beacuse the soft case will wear from the battery holder, straps etc.

Before I converted my soft packs to hard packs, I had them wrapped in good quality duct tape that could take all the tear and wear, and that was actually a good solution.